Purchase with More ConfidenceBecause you can't test products at drugstores, certain item—particularly foundation, which needs to match your skin tone—might be worth the splurge in a department store. Employees at the counter are typically experts at matching colors. Or, see what they suggest, request a sample and try to replicate it at a drugstore. Stores such as Sephora also hire specialists who can help with acne, rosacea and other skin problems.

Nab Luxe Trial-Size ProduceKiehl's and Sephora are known for being generous with trial sizes, but just about any brand will give you some if you request them. If a sample doesn't exist or if the store doesn't have one in stock, it's not uncommon for an employee to open a jar of a product you're interested in and dab some into a small container for you to take home.

Take Advantage of BonusesDepartment stores virtually never have sales on their brands, but they do offer gift-with-purchase promotions and special-collection kits throughout the year. The kits are often priced around $40 and contain close to $100 worth of makeup—steal if the palette is right for you. Befriend a salesperson and ask her to tell you the timing of promotions so you can plan your purchases wisely.

Check Your MailIf you have a department store credit card, read its statements. That's where the company typically alerts customers to in-store promotions.